// 身份证真实性验证
function testIDCard(value) {
  const vcity = {
    11: '北京',
    12: '天津',
    13: '河北',
    14: '山西',
    15: '内蒙古',
    21: '辽宁',
    22: '吉林',
    23: '黑龙江',
    31: '上海',
    32: '江苏',
    33: '浙江',
    34: '安徽',
    35: '福建',
    36: '江西',
    37: '山东',
    41: '河南',
    42: '湖北',
    43: '湖南',
    44: '广东',
    45: '广西',
    46: '海南',
    50: '重庆',
    51: '四川',
    52: '贵州',
    53: '云南',
    54: '西藏',
    61: '陕西',
    62: '甘肃',
    63: '青海',
    64: '宁夏',
    65: '新疆',
    71: '台湾',
    81: '香港',
    82: '澳门',
    91: '国外',
  }

  // 判断是否为空
  function isEmpty(card) {
    if (/^\s*$/.test(card)) {
      return true
    }
  }

  // 检查号码是否符合规范，包括长度，类型
  function isCardNo(card) {
    if (isEmpty(card)) {
      return true
    }
    // 这个代码表示身份证可以为空
    // 身份证号码为15位或者18位，15位时全为数字，18位前17位为数字，最后一位是校验位，可能为数字或字符X
    const reg = /(^\d{15}$)|(^\d{17}(\d|X)$)/
    if (!reg.test(card)) {
      return false
    }

    return true
  }

  // 取身份证前两位,校验省份
  function checkProvince(card) {
    if (isEmpty(card)) {
      return true
    }
    const province = card.substr(0, 2)
    if (vcity[province] === undefined) {
      return false
    }
    return true
  }

  // 检查生日是否正确
  function checkBirthday(card) {
    if (isEmpty(card)) {
      return true
    }
    const len = card.length
    if (len === 15) {
      // 身份证15位时，次序为省（3位）市（3位）年（2位）月（2位）日（2位）校验位（3位），皆为数字
      const re_fifteen = /^(\d{6})(\d{2})(\d{2})(\d{2})(\d{3})$/
      const arr_data = card.match(re_fifteen)
      const year = arr_data[2]
      const month = arr_data[3]
      const day = arr_data[4]
      const birthday = new Date(`19${year}/${month}/${day}`)
      return verifyBirthday(`19${year}`, month, day, birthday)
    } else if (len === 18) {
      // 身份证18位时，次序为省（3位）市（3位）年（4位）月（2位）日（2位）校验位（4位），校验位末尾可能为X
      const re_eighteen = /^(\d{6})(\d{4})(\d{2})(\d{2})(\d{3})([0-9X])$/
      const arr_data = card.match(re_eighteen)
      const year = arr_data[2]
      const month = arr_data[3]
      const day = arr_data[4]
      const birthday = new Date(`${year}/${month}/${day}`)
      return verifyBirthday(year, month, day, birthday)
    }
    return false
  }

  // 校验日期
  function verifyBirthday(year, month, day, birthday) {
    const now = new Date()
    const now_year = now.getFullYear()
    // 年月日是否合理
    if (birthday.getFullYear() === year && birthday.getMonth() + 1 === month && birthday.getDate() === day) {
      // 判断年份的范围（3岁到100岁之间)
      const time = now_year - year
      if (time >= 3 && time <= 100) {
        return true
      }
      return false
    }
    return false
  }

  // 校验位的检测
  function checkParity(card) {
    if (isEmpty(card)) {
      return true
    }
    // 15位转18位
    card = changeFivteenToEighteen(card)
    const len = card.length
    if (len === 18) {
      const arrInt = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2]
      const arrCh = ['1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2']
      let cardTemp = 0
      let i = 0
      let valnum = ''
      for (i = 0; i < 17; i++) {
        cardTemp += card.substr(i, 1) * arrInt[i]
      }
      valnum = arrCh[cardTemp % 11]
      if (valnum === card.substr(17, 1)) {
        return true
      }
      return false
    }
    return false
  }

  // 15位转18位身份证号
  function changeFivteenToEighteen(card) {
    if (isEmpty(card)) {
      return true
    }
    if (card.length === 15) {
      const arrInt = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2]
      const arrCh = ['1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2']
      let cardTemp = 0
      let i = 0
      card = `${card.substr(0, 6)}19${card.substr(6, card.length - 6)}`
      for (i = 0; i < 17; i++) {
        cardTemp += card.substr(i, 1) * arrInt[i]
      }
      card += arrCh[cardTemp % 11]
      return card
    }
    return card
  }

  const card = value
  // 校验长度，类型
  if (!isCardNo(card)) {
    return false
  }
  // 检查省份
  if (!checkProvince(card)) {
    return false
  }
  // 校验生日
  if (!checkBirthday(card)) {
    return false
  }
  // 检验位的检测
  if (!checkParity(card)) {
    return false
  }

  return true
}

export default {
  testIDCard,
}
